Disposable plastic food-service items are in increasingly widespread use for storing, serving and consuming food, due to their reasonably low-cost and the convenience they provide. Disposable food containers and articles inter alia include non-returnable containers such as yogurt cups and dinner entrée packaging; microwavable storage containers; and, general tableware items such as plastic plates, cups and cutlery. The increasing popularity of fast-food restaurant chains further fuels the demand for plastic tableware and takeout packaging. In addition to the fast food restaurants, caterers also prefer disposable food service items for the associated convenience, hygiene and competitive-costs. In this regard, it is important to note that replacement costs for disposable items such as cutlery articles are usually offset by clean-up costs (labor, materials and equipment) generally associated with permanent flatware. In addition, permanent flatware also has to be replaced due to inadvertent disposal or loss.
The presence of non-disposable metal cutlery along with other disposable food-service articles such as plates, cups and the like presents an unusual problem for restaurants and caterers. The problem stems from the loss of valuable metal cutlery into trash or refuse-containers along with disposable tableware and food remnants particularly during peak business hours and rush situations. As a result, the food establishment has to constantly replace expensive metal flatware. There has been a long-standing need to solve the problems relating to loss and inadvertent disposal of real silverware, as readily evidenced by the following excerpts taken from the patent literature:
U.S. Pat. No. 3,926,792, to Buford, filed on Aug. 23, 1973, in Column 1, lines 12 to 30 states:—“The food industry has long been plagued with the costly and time-consuming problem of separating valuable reusable items, such as metal tableware from solid waste, such as food, paper and other disposable items. This problem is prevalent in any food service facility, such as restaurants, cafeterias, schools, prisons, and so on, in which plates must be scraped and/or tableware separated from garbage by hand sorting or by scavenging, and especially in the airline industry where there is no opportunity for sorting in flight. Even when manual sorting or scavenging is carried out, it has been found that a large amount of tableware is lost. For example, a set of airline tableware only lasts about seven flights. It is obvious that continued replacement of tableware is not only expensive, but economically wasteful. Some restaurants have found that most missing tableware is lost, rather than taken by customers, and that such losses run as high as $1,300 on a traditionally heavy day.”
U.S. Pat. No. 4,367,138, to Kustas, filed on Jun. 8, 1981, in Column 1, lines 11-16 states:—“ . . . As is well-known in the restaurant business, the loss of silverware or stainless steel flatware is a very serious problem which costs restaurant owners large sums of money every year. The problem stems from careless kitchen help and the manner in which food and debris is removed from used dishes.”
U.S. Pat. No. 4,632,253, to Stromgren et al., filed on Dec. 6, 1984, in Column 1, lines 35-49 states:—“In conjunction with a waiter scrapping food waste from plates into a waste container, it quite often happens that cutlery accompanies the waste into the container. For obvious reasons, the waiter avoids putting his arm down into the waste container to retrieve the dropped item. Studies made in restaurant kitchens in hotels associated with several intercontinental hotel chains show that not only an occasional item of cutlery is lost in this way, but even the cutlery used by all the guests at a table may be accidentally tipped into the waste container together with waste food, particularly when the restaurant is busy and the waiter rushed. It must be regarded as natural that the waiter also avoids taking up the cutlery dropped into the waste container in such circumstances.”
In addition, market research conducted by Waddington North America, Inc., the assignee of the present invention, shows that caterers estimate a loss of 15% to 30% of permanent flatware annually.
Another problem that food caterers encounter is the ability to clean metal flatware utensils at certain locations and outdoor catering events. In preparation for such circumstances caterers tend to carry a large inventory of expensive metal cutlery. The use of disposable plastic cutlery for such catering events would eliminate the limitations with cleaning metal flatware, handling heavy metal cutlery or keeping a large inventory thereof. In addition, it is noteworthy that disposable cutlery offers significant handling advantages compared to its metal-counterparts. For example, a typical cutlery combination containing a fork, a knife, a tablespoon, and a teaspoon would weigh about 200 grams for metal flatware versus about 30 grams for premium plastic cutlery. Applying these weights to a hypothetical 250-person event would yield an overall weight for metal cutlery of about 110 lbs., as compared to only 16 lbs. for plastic cutlery.
After the tragic 9-11 terrorist attacks with hijacked airplanes and the potential threat resulting from misuse of stainless steel flatware as weapons, there has been an increased tendency for major airline organizations to utilize disposable plastic cutlery while serving meals during flights. However, the use of disposable plastic cutlery affects the image of the airline, especially in premium seating and higher priced flights. What is lacking in the industry is a silverware article that is authentic looking yet is made of plastic would allow the Airlines to preserve their upscale image, particularly in the premium passenger classes, while continuing to enhance flight safety and maintaining compliance with legal and regulatory mandates.
A significant number of upscale catering establishments utilize disposable plastic cups, plates, and bowls etc. for catering functions. However, there is a general preference for continued use of traditional metal cutlery, primarily because of a perception gap between disposable plastic cutlery articles and permanent flatware. Disposable cutlery articles are generally regarded as having less-than-classic appearance and not suited for an upscale presentation; while, permanent flatware is generally regarded as more upscale and having a superior image. This perception gap is not entirely due to the superior strength of permanent flatware. Although stainless steel cutlery or permanent flatware is stronger than plastic cutlery, heavy weight plastic cutlery is functionally adequate for most occasions. Thus, a primary obstacle for use of disposable plastic cutlery in upscale situations is the perception and the image associated with disposable plastic cutlery rather than its performance.
From the foregoing, it can be readily appreciated, that there is a need for cutlery and food-handling implements that offer the disposability and convenience of plastic cutlery and the upscale perception generally associated with permanent flatware. Bridging the perception gap between disposable plastic cutlery and permanent flatware would naturally lead to greater acceptance of disposable plastic cutlery for use in upscale situations, by caterers and other food-service establishments, where traditionally permanent flatware heretofore has been the only alternative.
With respect to plastic articles, there are a variety of methods for coloring and/or decorating plastic articles that have been employed in the art including—dyeing, pigmenting, printing, hot stamping, heat transfers, in-mold decorating, spray painting, and electroplating. Printing techniques have been further classified as silkscreen printing, gravure or offset printing, and pad transfer printing.
Coloring or pigmenting is one of the most common and inexpensive methods to modify or enhance the appearance of a plastic article. Coloring typically involves incorporating a pigment or a dye into the plastic resin that is used for molding plastic articles. Pigments can be in the form of solid color concentrates or in the form of liquid color. Metallic pigments are known in the art and are commercially available; however, it is the general experience of those skilled in the art that these metallic pigments do not impart an authentic metallic look. Furthermore, metallic pigments do not provide a plastic cutlery article that emulates the polished silver-like metallic appearance of fine cutlery or silverware. In fact, almost all commercial plastic tableware or cutlery articles made by utilizing a silver metallic pigment have a dull or grayish appearance. In addition, some of the formulations for metallic pigments have an odor which is less-than-desirable for a food-service item.
Printing with single or multi-colored inks is commonly used for decorating plastic articles. The types of inks that can be used with food service articles tend to be limited due to food contact, toxicity and environmental issues. In addition, at least some of the inks frequently require a protective overcoat to overcome food contact issues. Metallic inks are known in the art; however, metallic inks also have similar food contact drawbacks and are not adapted for use with food handling implements due to a variety of reasons. Firstly, it would be difficult to handle the three-dimensional shape of a fork or a spoon and to apply a uniform layer of metallic ink thereon in an economic or consistent manner. Secondly, metallic inks do not provide the characteristic reflective appearance of a polished stainless steel flatware item or similar metallic article. Thirdly, the appearance of metallic inks would be further marred by the necessity of adding a protective overcoat for safety and food contact purposes.
In-mold labeling or decorating refers to the technique for decorating a plastic article wherein a label is strategically placed inside the mold prior to molding and held against a mold face by vacuum or mechanical means, thereafter hot plastic resin is introduced into the mold to effect label adhesion onto the molded part; and, thereby the label and the molded part are integrated into a unified article. Although, it is conceivable that a metallic label can be devised for use in injection molding, in-mold labeling is mostly limited for parts that either have a planar surface or a smooth curved surface such as the outer wall of a cup. In-mold labeling is not readily or economically adaptable for articles having complex three dimensional shapes such as typical spoons or forks. In addition to general shape constraints, in-mold labeling operation on a cutlery article would further prove to be quite challenging due to the presence of ornate features or fine and intricate patterns frequently incorporated on the surface of a plastic cutlery article for commercial acceptance and in consistency with traditional flatware design trends. It would be readily recognized by those of ordinary skill that the presence of any delicate design features on the surface of the article would interfere with in-mold label adhesion, which in turn would lead to wrinkling of the label on the part surface and detract from the overall appearance of the cutlery article.
Heat transfers and hot-stamping techniques provide additional options for decorating plastic articles. In particular, metal foil stamping can provide an authentic metallic-look when strategically placed on a plastic surface. Once again these techniques are not suited for articles having complex three-dimensional geometry such as cutlery articles. Foil wrinkling and/or inconsistent adhesion in the intricate detail areas of a cutlery article limit the utility of the foil stamping process for obtaining disposable cutlery having the appearance of permanent flatware or authentic silverware.
Electroplating methods for metallizing plastic cutlery articles are undesirable due to the environmental impact associated with electroplating chemicals as is known in the art. In addition, not all plastics can be readily electroplated. Furthermore, electroplating offers several challenges in terms of handling and processing cutlery articles economically.
Various metallizing methods have been described in the art, including U.S. Pat. No. 5,022,554 that describes metallized tableware, such as plates, cups, etc., made of a paper substrate, a metallized plastic film joined to the substrate, and an FDA approved top coating over the plastic film. This method of obtaining a metallic-look food service items by laminating a metallized film is not readily applicable to cutlery due to the fact that most plastic cutlery is generally produced by the injection-molding process wherein the feedstock is thermoplastic resin pellets and not laminated film. The shortcomings of incorporating a metallic foil or label during injection molding plastic cutlery have been discussed herein above. Similar shortcomings would typically apply to the use of a laminated metallic film.
Other approaches to metallization such as those used by Quest et al. (U.S. Pat. Nos. 5,177,124 and 5,280,052) describe a utilitarian and/or decorative object and a method for forming plastic parts having a metallic outer face, appearance and hand. In this technique, a mixture of a liquid monomer, curing agent, a dispersion of metal particles and floatable particles are poured into a mold. The mold is then centrifuged to cause the metal particles to migrate towards the surface of the piece before the monomer polymerizes and hardens to bind the particles. After removal from the mold, the outer face of the piece is polished and buffed to remove the plastic skin from the metal surface, whereby the resultant plastic piece simulates the appearance of a solid metal piece. This method is generally too cumbersome for application to plastic cutlery as most plastic cutlery is either made of polystyrene and/or polypropylene which are thermoplastic polymeric materials and do not easily lend themselves to the teachings of the referenced art. In addition, the typical process for producing cutlery is injection molding and it is difficult and cost-prohibitive to rotate a heavy injection mold. And, finally the secondary step of cleaning and buffing the plastic piece is expensive and may be unacceptable for food-service use.
Various references are available on plating of plastic materials by chemical deposition techniques, electro-deposition techniques and/or a combination thereof. Some plating methods are described in U.S. Pat. Nos. 3,607,350; 3,629,922; 3,896,252; 3,962,494; 4, 4,610,895; 3,445,350; 4,039,714; 4,073,743; 4,195,117; and 4,810,333. These techniques are essentially wet processes and require that parts be brought into contact with solutions containing metal ions, which must then be washed off to remove any residual chemicals and for general hygiene reasons for a food service article. These processes are relatively unattractive for metallizing cutlery because of the high processing and environmental costs.
Thus, it can be readily established that there is a need for fine plastic cutlery that has an enhanced visual and commercial appeal. The improved plastic cutlery should be inexpensive, permitting simple disposal and not requiring separation from food refuse. Such an invention should be manufactured without environmental shortcomings generally associated with metal-plating wet processes. An improved plastic cutlery article should be fabricated primarily from plastic materials, yet have the appearance of genuine metal on the outer surface such that it is practically indistinguishable, at least visually, from a fine metal flatware or cutlery article.